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path: root/drivers/spi/spi_bitbang.c
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2010-07-03spi/bitbang: reinitialize transfer parameters for every messageBrian Niebuhr
This patch fixes the setup_transfer logic to account for the case where multiple messages to different SPI devices are in the queue simultaneously. With the current logic, the second message in the queue will end up using the transfer parameters for the previous message in the queue. The fix is to reinitialize the transfer parameters for each message rather than only once on the first message. Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-06-30spi: bitbang bugfix in message setupDavid Brownell
Bugfix to spi_bitbang infrastructure: make sure to always set transfer parameters on the first pass through the message's per-transfer loop. This can matter with drivers that replace the per-word or per-buffer transfer primitives, on busses with multiple SPI devices. Previously, this could have started messages using the settings left after previous messages. The problem was observed when a high speed chip (m25p80 type flash) was running very slowly because a low speed device (avr8 microcontroller) had previously used the bus. Similar faults could have driven the low speed device too fast, or used an unexpected word size. Acked-by: Steven A. Falco <sfalco@harris.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18spi: move more spi_setup() functionality into coreDavid Brownell
Move some common spi_setup() error checks into the SPI framework from the spi_master controller drivers: - Add a new "mode_bits" field to spi_master - Use that in spi_setup to validate the spi->mode value being requested. Setting this new field is now mandatory for any controller supporting more than vanilla SPI_MODE_0. - Update all spi_master drivers to: * Initialize that field * Remove current spi_setup() checks using that value. This is a net minor code shrink. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18spi: move common spi_setup() functionality into coreDavid Brownell
Start moving some spi_setup() functionality into the SPI core from the various spi_master controller drivers: - Make that function stop being an inline; - Move two common idioms from drivers into that new function: * Default bits_per_word to 8 if that field isn't set * Issue a standardized dev_dbg() message This is a net minor source code shrink, and supports enhancments found in some follow-up patches. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06spi: struct device - replace bus_id with dev_name(), dev_set_name()Kay Sievers
Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-28spi: replace remaining __FUNCTION__ occurrencesHarvey Harrison
__FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-13spi_bitbang: short transfer status fixJan Nikitenko
SPI controller drivers return number of bytes actually transfered from bitbang->txrx_bufs() method. This updates handling of short transfers (where the transfer size is less than requested): - Even zero byte short transfers should report errors; - Include short transfers in the total of transferred bytes; - Use EREMOTEIO (like USB) not EMSGSIZE to report short transfers Short transfers don't normally mean invalid message sizes, but if the underlying controller driver needs to use EMSGSIZE it can still do so. [db: fix two more minor issues] Signed-off-by: Jan Nikitenko <jan.nikitenko@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-08spi_bitbang: always grab lock with irqs blockedDavid Brownell
Fix a glitch reported by lockdep in the spi_bitbang code: it needs to consistently block IRQs when holding that spinlock. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16spi doesn't need class_deviceTony Jones
Make the SPI framework and drivers stop using class_device. Update docs accordingly ... highlighting just which sysfs paths should be "safe"/stable. Signed-off-by: Tony Jones <tonyj@suse.de> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17SPI controller drivers: check for unsupported modesDavid Brownell
Minor SPI controller driver updates: make the setup() methods reject spi->mode bits they don't support, by masking aginst the inverse of bits they *do* support. This insures against misbehavior later when new mode bits get added. Most controllers can't support SPI_LSB_FIRST; more handle SPI_CS_HIGH. Support for all four SPI clock/transfer modes is routine. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-16[PATCH] spi: destroy workqueue after spi_unregister_masterChris Lesiak
Fix a bug in the cleanup of an spi_bitbang bus. The workqueue associated with the bus was destroyed before the call to spi_unregister_master. That meant that spi devices on that bus would be unable to do IO in their remove method. The shutdown flag should have been able to prevent a segfault, but was never getting set. By waiting to destroy the workqueue until after the master is unregistered, devices are able to do IO in their remove methods. An added benefit is that neither the shutdown flag nor a wait for the queue of messages to empty is needed. Signed-off-by: Chris Lesiak <chris.lesiak@licor.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12[PATCH] SPI cleanup() method param becomes non-constHans-Peter Nilsson
I'd like to assign NULL to kfree()d members of a structure. I can't do that without ugly casting (see the PXA patch) when the structure pointed to is const-qualified. I don't really see a reason why the cleanup method isn't allowed to alter the object it should clean up. :-) No, I didn't test the PXA patch, but I verified that the NULL-assignment doesn't stop me from doing rmmod/insmodding my own spi_bitbang-based driver. Signed-off-by: Hans-Peter Nilsson <hp@axis.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12[PATCH] spi_bitbang(): use overridable setup_transfer() methodHans-Peter Nilsson
A small bug-fix for spi_bitbang: it must always call the setup_transfer function via the overridable pointer, not assume that its spi_bitbang_setup_transfer is sufficient. Otherwise, if all options in the transfers are default (0), the overrided function will never be called. Granted, the function replacing it must call spi_bitbang_setup_transfer, but it might also have other important things to do, even if the second argument (the spi_transfer) is NULL. Tested together with the other patches on the spi_crisv32_sser and spi_crisv32_gpio drivers (not yet in the kernel, will IIUC be submitted as part of the usual arch-maintainer-pushes). Signed-off-by: Hans-Peter Nilsson <hp@axis.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-07Revert "Driver core: convert SPI code to use struct device"Greg Kroah-Hartman
This reverts commit 2943ecf2ed32632473c06f1975db47a7aa98c10f. This should go through the SPI maintainer, it was my fault that it did not. Especially as it conflicts with other patches he has pending. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07Driver core: convert SPI code to use struct deviceGreg Kroah-Hartman
Converts from using struct "class_device" to "struct device" making everything show up properly in /sys/devices/ with symlinks from the /sys/class directory. Cc: <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-07[PATCH] slab: remove SLAB_KERNELChristoph Lameter
SLAB_KERNEL is an alias of GFP_KERNEL. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-22WorkStruct: make allyesconfigDavid Howells
Fix up for make allyesconfig. Signed-Off-By: David Howells <dhowells@redhat.com>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-05-16[PATCH] SPI: spi_bitbang: clocking fixesDavid Brownell
This fixes two problems triggered by the MMC stack updating clocks: - SPI masters driver should accept a max clock speed of zero; that's one convention for marking idle devices. (Presumably that helps controllers that don't autogate clocks to "off" when not in use.) - There are more than 1000 nanoseconds per millisecond; setting the clock down to 125 KHz now works properly. Showing once again that Zero (http://en.wikipedia.org/wiki/Zero) is still an inexhaustible number of bugs. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-05-16[PATCH] SPI: devices can require LSB-first encodingsDavid Brownell
Add spi_device hook for LSB-first word encoding, and update all the (in-tree) controller drivers to reject such devices. Eventually, some controller drivers will be updated to support lsb-first encodings on the wire; no current drivers need this. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-05-16[PATCH] SPI: Renamed bitbang_transfer_setup to spi_bitbang_setup_transfer ↵Kumar Gala
and export it Renamed bitbang_transfer_setup to follow convention of other exported symbols from spi-bitbang. Exported spi_bitbang_setup_transfer to allow users of spi-bitbang to use the function in their own setup_transfer. Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Cc: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-05-16[PATCH] SPI: per-transfer overrides for wordsize and clockingImre Deak
Some protocols (like one for some bitmap displays) require different clock speed or word size settings for each transfer in an SPI message. This adds those parameters to struct spi_transfer. They are to be used when they are nonzero; otherwise the defaults from spi_device are to be used. The patch also adds a setup_transfer callback to spi_bitbang, uses it for messages that use those overrides, and implements it so that the pure bitbanging code can help resolve any questions about how it should work. Signed-off-by: Imre Deak <imre.deak@nokia.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-13[PATCH] spi: use linked lists rather than an arrayVitaly Wool
This makes the SPI core and its users access transfers in the SPI message structure as linked list not as an array, as discussed on LKML. From: David Brownell <dbrownell@users.sourceforge.net> Updates including doc, bugfixes to the list code, add spi_message_add_tail(). Plus, initialize things _before_ grabbing the locks in some cases (in case it grows more expensive). This also merges some bitbang updates of mine that didn't yet make it into the mm tree. Signed-off-by: Vitaly Wool <vwool@ru.mvista.com> Signed-off-by: Dmitry Pervushin <dpervushin@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-13[PATCH] spi: add spi_bitbang driverDavid Brownell
This adds a bitbanging spi master, hooking up to board/adapter-specific glue code which knows how to set and read the signals (gpios etc). This code kicks in after the glue code creates a platform_device with the right platform_data. That data includes I/O loops, which will usually come from expanding an inline function (provided in the header). One goal is that the I/O loops should be easily optimized down to a few GPIO register accesses, in common cases, for speed and minimized overhead. This understands all the currently defined protocol tweaking options in the SPI framework, and might eventually serve as as reference implementation. - different word sizes (1..32 bits) - differing clock rates - SPI modes differing by CPOL (affecting chip select and I/O loops) - SPI modes differing by CPHA (affecting I/O loops) - delays (usecs) after transfers - temporarily deselecting chips in mid-transfer A lot of hardware could work with this framework, though common types of controller can't reach peak performance without switching to a driver structure that supports pipelining of transfers (e.g. DMA queues) and maybe controllers (e.g. IRQ driven). Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>